public class demo {
    private static int count = 0;
    public static String k = new String();
    public static void main(String[] args) throws InterruptedException {
        Thread t1 = new Thread(()-> {
            for (int i = 0; i <10000;i++) {
                synchronized (k) {
                    count++;
                }
            }
        });
        Thread t2 = new Thread(()->{
            for (int i = 0; i < 10000; i++) {
                synchronized (k){
                    count++;
                }
            }
        });
        t1.start();
        t2.start();
        t1.join();
        t2.join();
        System.out.println("count:"+ count);

    }
}
